In his application for a "Constant-Current Vertical Amplifier," Ser. No. 838,549, filed Oct. 3, 1977, the applicant discloses, inter alia, a circuit using a commercially available operational amplifier (op-amp) in a vertical deflection system. One of the advantages of that system is that the op-amp operates from a single rather than dual, -polarity voltage supply. However, in order to assure the maximum undistorted deflection output, it is necessary that the DC output of the op-amp be maintained at approximately one-half the supply voltage. This can be achieved by applying an appropriate DC voltage at the op-amp's noninverting input and applying substantial DC feedback between the amplifier's output and its inverting input. However, in circuits where it is necessary to apply the DC feedback through a long time-constant network, in order, for example, to maintain the op-amp's stability or noise immunity, the voltage at the op-amp's inverting input may not reach its quiescent level until an undesirable length of time has elapsed. During this time the op-amp's DC output will be sufficiently different fom one-half the supply voltage so that the vertical deflection output will be either distorted or collapsed. Disclosed herein is circuitry that assures that the DC voltage at the amplifiers inverting input reaches its quiescent level in a substantially shorter period of time.